Review Detail of Alyx_Sinclair in Solo Leveling(Only I level up)

This is an amazing story and the art is so meticulously drawn. It must take ages to get an episode out with all those monster bodies you have to draw. Though I have one question. If Sung Jin Woo was that really powerful guy in that memory/data thingy in chapter 129 Lucid Dream, what happened to him? Because that memory/data thing looked like a war from the past. If so did he get reincarnated and born again and lost his powers from his past life and have to start from scratch? It's really confusing. And in one of the panels from chapter 129 Lucid Dream it shows that he has two hearts. One purple and black, like his undead soldiers, and one normal human heart. How the hell did he get that purple heart? And what is it used for? I'm definitely sure it's not for pumping blood around the body.